It is known in the art of glassware manufacture to treat newly-formed bottles or other glass articles, so as to produce a substantial improvement in the strength and durability of the articles. One such treatment comprises flowing a quantity of gaseous treatment fluid into the hot newly-formed glassware while still hot. A chemical reaction takes place between the internal treatment gas and the hot glassware, substantially improving certain physical qualities of the glassware without significantly altering the appearance of the glassware. Details of such glassware internal treatment, including the composition and application of internal treatment gases, are known to those skilled in the art, one example being U.S. Pat. No. 3,249,246.
Because bottles and other glassware are subjected to such internal treatment to improve the strength and durability of the articles, it is important to assure that all such articles during a manufacturing run actually are subjected to the prescribed amount of treatment gas. It is also important that untreated glassware be clearly identifiable if the internal treatment system should malfunction for any reason, so that untreated glassware lacking the improved physical characteristics are not inadvertently comingled with the treated glassware. This later problem of identifying untreated glassware is particularly difficult with treatment systems in which the treated and untreated articles are substantially the same in physical appearance, so that the untreated articles cannot readily be identified and separated by a visual inspection process.
In addition to the foregoing problems, it is desirable to provide some measure of redundency for a glassware internal treatment system so that a failure of the system does not always necessitate the expense and trouble of shutting down the glassware production line or separating all untreated articles.